Method for operating a cleaning device as well as cleaning device and cleaning tool for carrying out the method

ABSTRACT

The invention relates to a method for operating a cleaning device with a drive motor which drives at least one cleaning tool. In order to develop the method further in such a manner that the degree of wear of the cleaning tool can be determined in a simple manner even when the cleaning tool is replaced, it is suggested in accordance with the invention that a wear value, which corresponds to the degree of wear of the cleaning tool present at the time the wear value is stored, be stored in a memory element of the cleaning tool and that this wear value be repeatedly updated. In addition, a cleaning device and a cleaning tool for carrying out the method are suggested.

This application is a continuation of international application numberPCT/EP2010/054022 filed on Mar. 26, 2010 and claims the benefit ofGerman application number 10 2009 018 121.0 filed on Apr. 9, 2009.

The present disclosure relates to the subject matter disclosed ininternational application number PCT/EP2010/054022 of Mar. 26, 2010 andGerman application number 10 2009 018 121.0 of Apr. 9, 2009, which areincorporated herein by reference in their entirety and for all purposes.

BACKGROUND OF THE INVENTION

The invention relates to a method for operating a cleaning device, inparticular for cleaning a surface, comprising a drive motor which drivesa cleaning tool.

In addition, the invention relates to a cleaning device and a cleaningtool for carrying out the method.

Cleaning devices with at least one cleaning tool which is driven by amotor, for example a roller brush or also a disk brush, can be used forthe purpose of cleaning a surface, in particular a floor surface. Thecleaning tools become worn during operation. For example, the cleaningbristles of a roller or disk brush will wear down over time. When amaximum degree of wear is reached, the cleaning tool should be replacedsince, otherwise, there is the risk of damage to the surface to becleaned and the cleaning result which can be achieved is inadequate.

The degree of wear of the cleaning tool will normally be controlledvisually by the user. This does, however, entail some difficulty incertain cases since the cleaning tool is often installed in a housing ofthe cleaning device and cannot easily be seen from the outside. Thecleaning tool is surrounded by housing and sealing elements in the caseof, for example, floor cleaning devices, in particular in the case ofscrubber driers.

In order to determine the degree of wear of a disk brush, it issuggested in DE 696 08 116 T2 to mount the disk brush on a verticallydisplaceable rod, the position of which can be detected by apotentiometer. With increasing wear of the disk brush, this is displacedever further downwards in the direction towards the floor surface to becleaned. This displacement will be detected by the potentiometer andforms a measure for the degree of wear of the disk brush. If the diskbrush is replaced, it is necessary to calibrate the position of the newdisk brush in order to ensure in this way that the signal of thepotentiometer corresponds to the actual degree of wear of the new diskbrush. The replacement of the disk brush, therefore, proves to be rathercomplicated for the user.

The object of the present invention is to provide a method of the typespecified at the outset as well as a cleaning device and a cleaning toolfor carrying out the method, wherein the degree of wear of the cleaningtool can be determined in a simple manner even when the cleaning tool isreplaced.

SUMMARY OF THE INVENTION

This object is accomplished in accordance with the invention, in amethod of the generic type, in that a wear value is stored in a memoryelement of the cleaning tool, said value corresponding to the degree ofwear of the cleaning tool present at the time the wear value is stored,and that this wear value is repeatedly updated.

With the method according to the invention, a cleaning tool is usedwhich has a memory element. A wear value, which corresponds to thecurrent degree of wear of the cleaning tool, can be stored in thismemory element. The stored wear value can be read out at a later pointin time. During further operation of the cleaning device, a new wearvalue, which represents the current wear of the cleaning tool, can bedetermined on the basis of the wear value read out and this new wearvalue can then be stored again in the memory element of the cleaningtool. If the cleaning tool is replaced by another cleaning tool whichlikewise has a memory element, the current wear value can be read out ofthe memory element of the cleaning tool which has been replaced and usedfor later updating.

The determination of the degree of wear of the cleaning tool proves tobe very simple even after the cleaning tool has been replaced since thecleaning tool carries a wear value with it in its memory element whichcorresponds to the degree of wear of the cleaning tool present at thetime the wear value was stored. This wear value can then be extrapolatedduring further use of the cleaning tool.

It is of advantage when the wear value stored in the memory element ofthe cleaning tool is read out when the cleaning device is switched on.The wear value read out can be displayed to the user, for example, on adisplay unit of the cleaning device. Therefore, the user need notnecessarily check the degree of wear of the cleaning tool visually priorto the start of a cleaning process.

The fact that the wear value stored in the memory element of thecleaning tool is read out when the cleaning device is switched on has,in addition, the advantage that the user can recognize immediatelywhether a cleaning tool has been installed or not. It is, namely,possible for a user to erroneously assume that a cleaning tool hasalready been installed and he can begin with the cleaning process.Instead, the cleaning device has, however, not been equipped with theappropriate cleaning tool. This can be displayed to the user in a simplemanner since it is not possible without a cleaning tool to read out itswear value.

Identification characteristics, which clearly identify the cleaningtool, are also preferably stored in the memory element of the cleaningtool. It can, for example, be recognized on the basis of theidentification characteristics what type of cleaning tool it is.

It is favorable when operating parameters of the cleaning device, forexample the rotational speed or the tool contact pressure, are set as afunction of the identification characteristics which have been read out.The tool contact pressure is, in this respect, the pressure which thecleaning tool exerts on the surface to be cleaned during operation ofthe cleaning device. In one advantageous embodiment the tool contactpressure can be predetermined and varied by the cleaning device, forexample as a function of the type of cleaning tool used.

In one preferred development of the method according to the invention,the current wear value of the cleaning tool is determined and stored inthe memory element of the cleaning tool when the cleaning device isswitched off. If the cleaning tool is used again at a later point intime, its current wear value can be taken from the memory element.

Alternatively or in addition, it may be provided for the current wearvalue to be determined at time intervals during the running operation ofthe cleaning device and stored in the memory element of the cleaningtool. It may be provided, in particular, for the current wear value tobe determined at equal time intervals and stored in the memory element.This has the advantage that a wear value is always stored in the memoryelement, even with longer operation of the cleaning device, whichdiffers only insignificantly from the actual degree of wear present. Thestored wear value therefore corresponds practically and at any point intime to the degree of wear of the cleaning tool actually present.

It may be provided for the degree of wear of the cleaning tool to bedetected by means of a sensor for the purpose of determining the wearvalue.

It is favorable when the wear value is determined by way of calculation.It is of particular advantage when the wear value is determined usingoperating data of the cleaning device, in particular using operatingdata of the drive motor.

The motor current of the drive motor can be detected in one advantageousembodiment for the purpose of determining the wear value. The motorcurrent and, therefore, the current consumption of the drive motor aredependent on the pressure, with which the cleaning tool is pressedagainst the surface to be cleaned and how rough the surface is. Thegreater the contact pressure and the rougher the surface, the greaterthe motor current and the greater the wear on the cleaning tool. Themotor current can, therefore, be included in the mathematicaldetermination of the wear value which represents a measure for theactual degree of wear of the cleaning tool. The motor current can bedetected electrically without mechanical or electromechanical sensorsneeding to be used for this purpose.

It is favorable when a temporal average value of the motor current isdetermined and this used for the purpose of determining the wear valueof the cleaning tool.

The degree of wear of the cleaning tool is influenced by the runningtime of the cleaning tool. The longer the cleaning tool is in operation,the greater its degree of wear generally is. It is, therefore, favorablewhen the running time of the cleaning tool is determined for the purposeof determining the wear value. This determination of the running timecan take place electronically without mechanical or electromechanicalsensors being required for this purpose.

In one preferred development of the method according to the invention,the motor current of the drive motor is integrated over the running timeof the cleaning tool for the purpose of determining the wear value. Thevalue of the integral thus determined forms a wear value whichrepresents a measure for the actual degree of wear of the cleaning tooland can be stored in the memory element of the cleaning tool.

It may be provided, for example, for the product resulting from thecurrent motor current and the length of the time interval to be formedat time intervals and these product values added together. The productvalues added together correspond essentially to the time integral of themotor current and form a measure for the degree of wear of the cleaningtool. This measure can be stored in the memory element of the cleaningtool in the form of a wear value. At the beginning of a cleaningprocess, the last wear value stored can be read out of the memoryelement and a new wear value can be determined on the basis of this wearvalue during further operation of the cleaning tool in that the additionor integral formation specified above will be continued.

It is of particular advantage when the temporal average value of themotor current of the drive motor is integrated over the running time ofthe cleaning tool for the purpose of determining the wear value.Short-term fluctuations in the motor current, which have only aninsubstantial or even no influence on the degree of wear of the cleaningtool, can be compensated as a result.

It is favorable when the wear value is transmitted wirelessly to thememory element of the cleaning tool and is read out wirelessly. Agalvanic connection between a control unit of the cleaning device andthe memory element of the cleaning tool can be omitted, as a result.This reduces the susceptibility to interference of the datatransmission.

It may be provided for the wear value to be transmitted to the memoryelement by radio and also read out by radio. For this purpose, thecleaning tool can have a transponder, i.e. a radio communication elementwhich accepts and answers incoming signals. A wireless transmissionchannel can be achieved between the memory element of the cleaning tooland the control unit of the cleaning device by means of the transponder.The transponder comprises the memory element. It is favorable when thetransponder also has a control logic. In addition, it comprises atransmitting and receiving aerial, for example an aerial coil. Thecontrol unit of the cleaning device can have a read/write unit which isassociated with the transponder and with the aid of which the memoryelement is readable and writable wirelessly.

It may be provided for the transponder to be equipped with its owncurrent source.

Combinations consisting of a transponder and a read/write unit are knownto the person skilled in the art in general under the term RFIDtechnology (radio frequency identification).

In one advantageous embodiment, the current wear value is compared to apredetermined wear value and an operating function of the cleaningdevice will be initiated as a function of the result of the comparison.The specified wear value can, for example, be a maximum value whichshould not, if possible, be exceeded. A specific reaction, i.e. aspecific operating function, can be initiated as a function of thedifference between the current wear value and the predetermined wearvalue.

It may be provided, for example, for the fact that a predetermined wearvalue has been reached or exceeded to be indicated to a user of thecleaning device.

Alternatively or in addition, it may be provided for at least oneoperating parameter of the cleaning device to be controlled as afunction of the result of the comparison between the current wear valueand the predetermined wear value. For example, the tool contact pressureand/or the rotational speed of the cleaning tool and/or the travelingspeed of the cleaning device can, inter alia, be made dependent on themagnitude of the current wear value in comparison with the predeterminedwear value. If the current wear value exceeds the predetermined wearvalue, the tool contact pressure or the rotational speed can, forexample, be reduced.

It is favorable when the fact that the predetermined wear value has beenexceeded is indicated at repeated time intervals. It may be provided, inparticular, for the fact that the predetermined wear value has beenexceeded to be indicated repeatedly at ever shorter time intervals. Sucha procedure aims at making the user clearly understand that thedetermined wear value exceeds the predetermined wear value.

It may be provided, for example, for the user, once it has beenindicated to him that a predetermined wear value has been reached orexceeded, to acknowledge the warning and continue the cleaning process.The user can, as a result, terminate a cleaning process, for example,before he replaces the worn cleaning tool. The fact that the wear valuehas been exceeded can be indicated to the user at time intervals,wherein the user can again acknowledge this warning. In this respect, itis favorable when the fact that the predetermined wear value has beenexceeded is indicated at ever shorter time intervals so that the usermust acknowledge the warning at ever shorter time intervals. The risk ofthe cleaning tool or also the surface to be cleaned being damaged isreduced as a result.

The predetermined wear value is preferably stored in the memory elementof the cleaning tool. As a result, a specific wear value can be presetfor each cleaning tool in a simple manner.

As mentioned at the outset, the object of the present invention is alsoto provide a cleaning device for carrying out the method specifiedabove. This object is accomplished in accordance with the invention by acleaning device which has a drive motor and at least one cleaning toolwhich can be driven by the drive motor, wherein the cleaning tool has awritable and readable memory element for storing a wear valuecorresponding to the degree of wear of the cleaning tool and wherein acurrent wear value can be determined using the wear value last storedand operating data of the cleaning device and can be stored in thememory element of the cleaning tool.

The cleaning tool therefore carries a memory element with it, in which awear value corresponding to the degree of wear of the cleaning tool isstored. The cleaning tool is worn down further each time it is used,i.e. the actual degree of wear changes. In order to take this changeinto account, a new wear value can be determined and stored in thememory element. The old wear value can be overwritten. The wear valuepreviously stored and operating data of the cleaning device, inparticular of the drive motor, can be used for determining the new wearvalue.

The memory element of the cleaning tool is favorably writable andreadable wirelessly.

As mentioned, it may be provided, for example, for the cleaning tool tohave a transponder which comprises the memory element. A read/write unitof the cleaning tool can be associated with the transponder for thereading and writing of the memory element. The read/write unit can beconnected to a control unit of the cleaning tool.

The motor current of the drive motor and the running time of thecleaning tool can preferably be determined and the motor current can beintegrated over the running time of the cleaning tool. As mentioned, awear value, which corresponds to an actual degree of wear of thecleaning tool, can be calculated in a simple manner as a result.

It is of advantage when the wear value previously stored in the memoryelement of the cleaning tool can be updated automatically and theupdated wear value can be stored automatically in the memory element ofthe cleaning tool when the cleaning device is switched off. As a result,it can be ensured that a wear value, which corresponds to the degree ofwear of the cleaning tool present after a successful cleaning process,is stored in the memory element of the cleaning tool following acleaning process. If the cleaning tool is put into operation again at alater point in time, the wear value last stored can be read out and canform the basis for the extrapolation of the wear value.

The object underlying the present invention is also to provide acleaning tool for carrying out the method specified above. This objectis accomplished in accordance with the invention by a cleaning toolwhich has a memory element, in which identification characteristicswhich clearly identify the cleaning tool are stored and in which a wearvalue corresponding to the current degree of wear of the cleaning toolcan be stored. The cleaning tool can be clearly identified by readingthe identification characteristics and a wear value which corresponds tothe current degree of wear of the cleaning tool can be stored in itsmemory element. If the cleaning tool is used in a cleaning device, theidentification characteristics and the wear value can be read out. A newwear value can then be determined on the basis of the wear value readout, at the latest after use of the cleaning tool has finished, andstored in the memory element.

The identification characteristics can favorably not be altered by aread/write unit of the cleaning tool.

An identification number is preferably used as identificationcharacteristic.

The cleaning tool favorably comprises a base member, from which cleaningbristles project on the outside and which has a cavity, in which thememory element is arranged. The memory element is, therefore, protectedin a simple manner from any mechanical interference. The cleaning toolcan be configured, for example, as a roller brush or as a disk brush andused preferably in a sweeper machine or scrubber drier.

The following description of one preferred embodiment of the inventionserves to explain the invention in greater detail in conjunction withthe drawing.

BRIEF DESCRIPTION OF THE DRAWING

The single Figure of the drawing shows schematically a cleaning deviceaccording to the invention with a cleaning tool according to theinvention.

DETAILED DESCRIPTION OF THE INVENTION

The cleaning device 10 according to the invention, which is illustratedschematically in the drawing, comprises a drive motor 12 which iscontrolled by a control unit 14 and drives a cleaning tool in the formof a roller brush 16. For this purpose, a drive disk 20 is non-rotatablyheld on a motor shaft 18 and is coupled via a drive belt 22 to a beltpulley 24. The belt pulley 24 is non-rotatably connected to a driveshaft 26 which is rotatably mounted on a bearing sleeve 32 of a housing34 of the cleaning device 10 by means of a first ball bearing 28 and asecond ball bearing 30 and bears a cylindrical base member 36 of theroller brush 16.

The base member 36 has a cavity 38, in which a transponder 40 with anaerial 42 and a memory element 44 is arranged. On the outside, aplurality of cleaning bristles 46 project radially outwards from thebase member 36. A surface can be cleaned with the cleaning bristles 46,in particular a floor surface. In the embodiment illustrated, thecleaning device 10 is configured as a scrubber drier or as a sweepermachine.

The housing 34 has a cover wall 48 which covers the roller brush 16 andbears on its upper side 50 facing away from the roller brush 16 aread/write unit 52 which is connected to the control unit 14. The memoryelement 44 of the transponder 40 is readable and writable wirelessly viathe read/write unit 52.

The control unit 14 is in electrical connection with a display device54, on which information can be displayed to the user. An identificationnumber, which clearly identifies the roller brush 16, cannot be alteredby the read/write unit and is read out of the non-volatile memoryelement 44 by means of the read/write unit 52 when the cleaning device10 is switched on, is stored in the memory element 44 of the rollerbrush 16. The control unit 14 recognizes in this way what type of rollerbrush 16 is being used during a cleaning process and the control unit 14can determine the running time of the respective roller brush 16 bymeans of a clock 56 and indicate this on the display device 54. Inaddition, the control unit 14 detects the motor current of the drivemotor 12. The control unit 14 calculates a temporal average value of themotor current by means of a calculating unit 58 at short time intervals,for example at intervals of one minute, and integrates the temporal timevalue of the motor current over the running time of the roller brush 16.The value of the integral calculated forms a wear value which representsa measure for the actual degree of wear of the roller brush 16. Thiswear value will be compared by a comparison element 60 of the controlunit 14 with a predetermined wear value of the roller brush 16 which isstored in the memory element 44, cannot be changed by the read/writeunit 52 and is the maximum allowed. When the predetermined wear value isreached or exceeded, this will be indicated to the user on the displaydevice 54. The user can then acknowledge the warning by means of aninput unit 62 so that the cleaning operation can be continued. Duringfurther operation of the roller brush 16, the fact that thepredetermined wear value has been exceeded will be indicated to the useragain on the display unit 54 at ever shorter time intervals and thismust be acknowledged by the user each time in order to be able tocontinue the cleaning operation. Otherwise, the cleaning operation willbe interrupted.

As mentioned, the integral of the average motor current over the runningtime of the roller brush 16 forms the calculated wear value. This canalso be calculated as the sum of the products of the motor currentaveraged each time over a time interval and the length of the respectivetime interval. When the cleaning device 10 is switched off, the wearvalue currently calculated will be stored in the memory element 44 ofthe roller brush 16. In addition, it may be provided for the respectivecurrent wear value to be stored in the memory element 44 at timeintervals during the running cleaning operation.

A wear value is thus stored in the memory element 44 of the roller brush16 which corresponds to the degree of wear of the roller brush 16. Ifthe cleaning device 10 is switched on, the wear value stored in thememory element 44 will be read out in addition to the identificationnumber already mentioned. At the beginning of a cleaning process, thecontrol unit 14 therefore receives from the memory element 44, on theone hand, the information that a roller brush 16 is installed and whatsort of roller brush 16 it is; on the other hand, the memory element 44is given a measure for the current degree of wear of the roller brush16. The degree of wear stored in the memory element 44 then forms thebasis for the updating of the degree of wear during further use of theroller brush 16. For this purpose, the value of the average motorcurrent integrated over the subsequent cleaning time will be added tothe wear value read out from the memory element 44 when the cleaningdevice 10 is switched on. The sum thus obtained then forms the new wearvalue which will be stored in the memory element 44 when the cleaningdevice 10 is switched off.

If no identification number and/or no previous wear value is readable bymeans of the read/write unit 52 when the cleaning device 10 is switchedon, this will be indicated to the user on the display unit 44. The lackof these values indicates that either no roller brush 16 whatsoever hasbeen installed or, however, that the transponder 40 of the roller brush16 is defective.

The provision of the roller brush 16 with integrated transponder 40therefore gives the control unit 14 of the cleaning device 10 thepossibility to determine the running time of the roller brush 16 andalso a wear value which represents a measure for the actual degree ofwear of the roller brush 16. This wear value can be updated repeatedlyand stored in the memory element 44. Since different roller brushes areoften required for different cleaning tasks, the respective wear valuecan be transmitted to the control unit 14 of the cleaning device 10 in asimple and contact-less manner when the roller brushes are replaced.

1. Method for operating a cleaning device, in particular for cleaning asurface, comprising a drive motor driving at least one cleaning tool,wherein a wear value is stored in a memory element of the cleaning tool,said value corresponding to the degree of wear of the cleaning toolpresent at the time the wear value is stored, and wherein this wearvalue is repeatedly updated.
 2. Method as defined in claim 1, whereinthe wear value stored in the memory element of the cleaning tool is readout when the cleaning device is switched on.
 3. Method as defined inclaim 1, wherein identification characteristics clearly identifying thecleaning tool are stored in the memory element of the cleaning tool. 4.Method as defined in claim 1, wherein the current wear value isdetermined and stored in the memory element of the cleaning tool whenthe cleaning device is switched off.
 5. Method as defined in claim 1,wherein the current wear value is determined at time intervals duringthe running operation of the cleaning device and stored in the memoryelement of the cleaning tool.
 6. Method as defined in claim 1, whereinthe wear value is determined using operating data of the cleaningdevice.
 7. Method as defined in claim 1, wherein the motor current ofthe drive motor is detected for the purpose of determining the wearvalue.
 8. Method as defined in claim 1, wherein the running time of thecleaning tool is determined for the purpose of determining the wearvalue.
 9. Method as defined in claim 1, wherein the motor current of thedrive motor is integrated over the running time of the cleaning tool forthe purpose of determining the wear value.
 10. Method as defined inclaim 1, wherein the temporal average value of the motor current of thedrive motor is integrated over the running time of the cleaning tool forthe purpose of determining the wear value.
 11. Method as defined inclaim 1, wherein the wear value is transmitted wirelessly to the memoryelement of the cleaning tool and is read out wirelessly.
 12. Method asdefined in claim 1, wherein the current wear value is compared to apredetermined wear value and at least one operating function of thecleaning device is controlled as a function of the result of thecomparison.
 13. Method as defined in claim 12, wherein operatingparameters of the cleaning device are controlled as a function of theresult of the comparison.
 14. Method as defined in claim 1, wherein thefact that a predetermined wear value has been reached or exceeded isindicated to a user of the cleaning device.
 15. Method as defined inclaim 14, wherein the fact that the predetermined wear value has beenexceeded is indicated at repeated time intervals.
 16. Method as definedin claim 14, wherein the predetermined wear value is stored in thememory element of the cleaning tool.
 17. Cleaning device for carryingout the method as defined in claim 1, comprising a drive motor and atleast one cleaning tool drivable by the drive motor, wherein thecleaning tool has a writable and readable memory element for the storageand read-out of a wear value corresponding to the degree of wear of thecleaning tool, and wherein a current wear value is determinable usingthe wear value last stored and operating data of the cleaning device andis storable in the memory element of the cleaning tool.
 18. Cleaningdevice as defined in claim 17, wherein the memory element of thecleaning tool is writable and readable wirelessly.
 19. Cleaning deviceas defined in claim 17, wherein the cleaning tool has a transpondercomprising the memory element.
 20. Cleaning device as defined in claim17, wherein the motor current of the drive motor and the running time ofthe cleaning tool are determinable and the motor current is integratableover the running time of the cleaning tool.
 21. Cleaning device asdefined in claim 17, wherein the wear value previously stored in thememory element of the cleaning device is adapted to be updatedautomatically and the updated wear value automatically stored in thememory element of the cleaning tool when the cleaning device is switchedoff.
 22. Cleaning tool for carrying out the method as defined in claim1, wherein the cleaning tool has a memory element, identificationcharacteristics clearly identifying the cleaning tool being stored insaid memory element and a wear value corresponding to the current degreeof wear of the cleaning tool being storable in said memory element. 23.Cleaning tool as defined in claim 22, wherein the cleaning toolcomprises a base member, cleaning bristles projecting from said memberon the outside and said member having a cavity, the memory element beingarranged therein.